Taliban militants attacked the main Afghan election commission's headquarters Saturday in Kabul, opening fire on the compound with rocket-propelled grenades and heavy machine guns from a house outside its perimeter wall, according to police.
It's the latest in a series of high-profile attacks that come as the Islamic militant movement steps up a campaign of violence to disrupt presidential elections, which are due to be held in a week.
A spokesman for the Independent Election Commission said security already had been increased around the compound because an attack had been widely expected, and no casualties have been reported.
Explosions were heard when the attack started, according to the spokesman Noor Mohammed Noor, but he did not know what caused them.
Kabul police chief Mohammad Zahir Zahir said three or four attackers were holed up in a neighboring house that had been empty when they occupied it. He said the house is about 800 meters (yards) away from the headquarters, which is inside a walled off compound guarded by a series of watch towers and checkpoints.
He said police were firing at the building from several directions and had the attackers contained.
Taliban spokesman Zabihullah Mujahid claimed responsibility for the attack but described what would have been a much more ambitious assault, claiming a suicide bomber and gunmen had stormed the IEC compound.
He said there was a meeting between the IEC and election observers, including foreigners, at the time of the attack. The Taliban frequently exaggerate in their statements and a meeting could not immediately be confirmed.
It would have been extremely difficult for the attackers to penetrate the tight security, but the Taliban have staged a number of assaults aimed at showing they are able to strike at will.
On Tuesday, the Taliban also struck another IEC office on the edge of Kabul, with a suicide bomber detonating his vehicle outside while two gunmen stormed into the building, killing four people and trapping dozens of employees inside.
The Taliban also have stepped up attacks on foreigners in the Afghan capital, suggesting that they are also shifting tactics to focus on civilian targets that aren't as heavily protected as military and government installations.
The Taliban targeted an American charity, the Roots of Peace, and a nearby day care center late Friday in the Afghan capital, sending foreigners - including women and children - fleeing while Afghan security forces battled the gunmen. Officials said two Afghan bystanders were killed - a girl and a driver.
Gunmen slipped through security last week into a luxury hotel in Kabul on March 20 with pistols and ammunition hidden in their shoes, then opened fire, killing nine people, including two Afghan children who were dining in the restaurant.
A Swedish journalist was shot to death on the street in a relatively affluent area earlier this month, and a Lebanese restaurant popular with foreigners was attacked by a suicide bomber and gunmen in January.